Comparative Study of Crop Water Productivity at Farm Level under Public and Civil Canal Irrigation Systems in Peshawar, Pakistan

Agriculture consumes more water than any other human activity. In Pakistan, the contributionof irrigated agriculture is more than 90%, thus the sustainable water supply to meet thefood and fibre demand of the ever increasing population is a big challenge. Increase in crop waterproductivity (CWP) is one of the most important options for sustainable use of water resources insemi-arid environment. A field study was conducted during Rabi 2010-11 and Kharif 2011 cropseasons to compare the CWP of main crops (wheat, sugarcane, maize and tomato) under public and civil canal irrigation systems in Peshawar Valley. For this purpose, 18 farms were selected under public canal system and 13 under civil canal systems. Results revealed that average CWP of wheat, maize, sugarcane and tomato was 0.96, 1.11, 3.31, 3.61 kg m^-3 under public and 0.90, 0.77, 2.36, 2.98 kg m^-3, under civil system, respectively. In public canal system, the average CWP of the selected crops was 7, 40, 44 and 21% higher than civil canal system, respectively. Low CWP in civil canal system was mainly attributed to over irrigation (because of high water allowance). Quantitative analysis of the yield per unit volume of water applied was carried out using dummy-regression model. The difference in means for maize, sugarcane and tomato crop was found highly significant while in case of wheat it was non-significant. This study concludes that the public system remained more productive with high CWP at farm level for all the major crops. However, there is a great potential for increasing CWP under civil system by rationalizing the water allowance.